Quintus is 17. Weighs 5kg (his healthy weight, which he is at now). He has severe arthritis so doesn't move much. Hops on the armchair, on the bed, walks to water-bowl, litterbox. Regularly (once or twice a day, but some days no) asks to go out, which means I carry him downstairs, put him down in front of the building, he walks a few steps, sniffs the air, hangs out, tries to eat some grass (no! bloody poop!), and after a few minutes walks back in and climbs up the flight of stairs to the flat. I've found various guidelines and had estimated that about 300 kcal would be good for him. His BG has dropped now and he's eating less (normal it seems, good!), he's put on some weight (the 300g he had lost), and I'm trying to figure out what the right amount of food is, and worrying that it's too little. Like, would 200 kcal be too little? Some examples of how many calories similarly inactive old cats are eating might help. I know ECID.